One-dimensional polymer-derived ceramic nanowires with electrocatalytically active metallic silicide tips as cathode catalysts for Zn–air batteries

Abstract

New intermetallic silicide catalysts for Zn–air batteries facilitate ORR/OER kinetics and deliver peak power densities of 59 mW cm−2 and 1200 cycles.

Iron, Cobalt, and Nickel Phthalocyanine Tri-Doped Electrospun Carbon Nanofibre-Based Catalyst for Rechargeable Zinc–Air Battery Air Electrode

“…In the present work, the lowest ∆E value of 0.89 V was obtained in the case of FeCoNi-CNF catalyst, which is ca. 100 mV higher compared to the ∆E value found in the case of polymer-derived ceramic nanowire catalysts with metallic silicide tips in our previous investigation of RZAB air electrode catalysts [46]. The dual-doped TM Pc functionalized CNT-based materials have shown even better ∆E values (0.76-0.84 V) in recent papers [40,71].…”

“…Nevertheless, it should be mentioned that the Zn-electrode area can play a crucial role in the measured P max value, which highlights the necessity to include the comparison curve with commercial PGM catalyst [ 47 , 80 ]. Also, the total discharge curve at 20 mA cm −2 was recorded for primary batteries with Pt-Ru/C and FeCoNi-CNF air electrodes to calculate the specific capacity according to the amount of consumed Zn electrode ( Figure 8 b) [ 46 ]. Specific capacities of 695 and 407 mAh g Zn −1 were obtained for Pt-Ru/C and FeCoNi-CNF, respectively, while the theoretical specific capacity is 820 mAh g Zn −1 [ 4 ].…”

“…A three-electrode system was used with the NPMC-coated GC as the working electrode, carbon rod as a counter electrode, and saturated calomel electrode (SCE) as a reference electrode. The reported potentials were converted from vs. SCE to vs. reversible hydrogen electrode (RHE) [ 46 ]. Cyclic voltammetry (CV) and rotating disc electrode (RDE) methods were employed for the electrochemical measurements using an Autolab potentiostat/galvanostat PGSTAT30 (Metrohm Autolab, Utrecht, The Netherlands) and Nova 2.1 software.…”

“…The polarisation curves for ORR were recorded in the cathodic direction, while the polarisation curves for OER were recorded in the anodic direction. The ORR and OER polarisation curves were IR compensated using the data obtained with electrochemical impedance spectroscopy [ 46 ].…”

Polymer‐derived ceramics for electrocatalytic energy conversion reactions

“…Due to synergistic effects between in situ grown CNTs and intermetallic nickel silicides (Ni 31 Si 12 and Ni 2 Si), Ni-containing PDC monoliths exhibited better bifunctional activities than other metal-based PDC composites with respect to both OER and ORR, with a low ΔE value of 1.20 V. Based on their discovery that transition metal nanoparticles can initiate the growth of CNTs within the porous PDCs architecture, the same authors further prepared metal-containing PDC nanowires decorated with intermetallic silicide tips by applying azodicarbonamide (ADA) as an extra foaming agent and increasing the pyrolysis temperature. 152 This ADA is capable of influencing the rheological properties of the preceramic polymer and its decomposition behavior, thereby changing the structure of the PDCs. The electrochemical results demonstrated that all the metal-containing PDCs (Ni/PDC, Co/PDC, and Fe/PDC) performed as excellent ORR/OER bifunctional catalysts.…”